Take a look at the above image and what do you see? Is it Albert Einstein or Marilyn Monroe?
ASAP Science recently dove into the topic of vision and provided this Monroe/Einstein GIF to illustrate low and high spacial frequency.
The secret to your success in this test is to see Einstein as soon as possible. The sooner you realize the image is actually the brilliant scientist, the healthier your eyes.
This video explains the test in detail and why it’s important: